首先，让我们看看delete_attachment 在堆芯中点火。这是在网上发生的5062 属于wp-includes/post.php 在wp_delete_attachment 作用以下是相关片段：

/**
 * Fires before an attachment is deleted, at the start of wp_delete_attachment().
 *
 * @since 2.0.0
 *
 * @param int $post_id Attachment ID.
 */
do_action( \'delete_attachment\', $post_id );

wp_delete_object_term_relationships($post_id, array(\'category\', \'post_tag\'));
wp_delete_object_term_relationships($post_id, get_object_taxonomies($post->post_type));

我们可以看到WordPress core正在调用do_action - 此方法不关心返回的内容；不像apply_filters, do_action 只需触发一个钩子，然后不管返回什么值，处理都将继续。进一步了解wp_delete_attachment, 似乎没有办法“短路”此过程并阻止删除附件。

Except, 从技术上讲，您可以使用PHPdie 或exit 语句以结束脚本的处理，这将有效防止文件被删除。

function action_maybe_delete( $id ) {
    echo "Let\'s not delete Attachment id: " . $id ;
    // prevent the attachment from actually being deleted
    if( 1 == 1 ) { // made up condition
        die; // Prevent the script from continuing.
    }
};
// add the action
add_action( \'delete_attachment\', \'action_maybe_delete\', 10, 1 ); ?php